Photopolymerization of ethylenically unsaturated organic compounds

ABSTRACT

A process for the photopolymerization of ethylenically unsaturated organic compounds, is disclosed, which comprises irradiating with actinic light a composition comprising a photopolymerizable ethylenically unsaturated organic compound and as a photopolymerization initiator a compound containing at least one diazosulfone group, said compound corresponding to one of the formulas: X-SO2-N N-Y and X&#39;&#39;-SO2-N N-Z-N N-SO2

D United States Patent 1 3,617,280

[72] Inventors Harald Huckstadt, Cologne, Stammheim; [50] Field ofSearch 96/66.3, Wilhelm Saleck, Schild gen; 107 August Randolph,Leverkusen; Erwin Ranz, Leverkusen, all of Germany [21] Appl. No.818,381 [22] Filed Apr. 22, 1969 [56] References Cited [45] PatentedNov. 2, 1971 [73] Assignee 'AGFA-Gevaert Aktiengesellschalt, UNITEDSTATES PATENTS Leverkusen, Germany 3,062,646 11/1962 Dann et a1 96/1073,471,296 10/1969 Huckstadt et al 96/107 Primary Examiner- Norman G.Torchin Assistant Examiner-Richard E. Fichter [54] SILVER BROMIDEEMULSION Attorneys-Connolly and Hutz SENSITIZED WITH 1,4,TRIAZINES 10Claims, N0 Drawings [52] US. Cl 96/66.3, ABSTRACT: The present inventionrelates to a process for 107 increasing the sensitivity of photographicsilver bromide [51] Int. Cl Go3c 5/30, emulsions by developing theemulsions in the presence of 1/28 thiomorpholine compounds.

SILVER BROMIDE EMULSION SENSITIZED WITH 1,4,TRIAZINES A number ofmethods have previously been described for increasing the'sensitivity ofphotographic silver halide emulsions. The incorporation of certaincolored compounds or dyes in the emulsions increases the optical rangeof sensitivity, and for this reason such dyes are commonly referred toas optical or spectral sensitizing dyes. It is also well known toincrease the sensitivity of photographic emulsions by addition of sulfurcompounds capable of reacting with silver salts to form silver sulfide,or by addition of reducing agents (compounds of these types are alsonaturally present in gelatin), or with salts of gold or other noblemetals, or with combinations of two or more of the'aforementionedcompounds generally known as chemical sensitizers. Such chemicalsensitizers are believed to react with the silver halide to form, on thesurface of the silver halide, minute amounts of silver sulfide or ofsilver or of other noble metals, and these processes are capable ofincreasing the sensitivity of emulsions by very large factors. Theprocess of chemical sensitization, however, reaches a definite limitbeyond which further addition of sensitizer, or of further digestionwith the sensitizer present, merely increases the fog of thephotographic emulsion leaving the sensitivity constant or evendecreasing it.

Other chemical sensitizers are higher polyethyleneglycols having amolecular weight of at least 1500. Lower polyethyleneglycols have no oronly very small effect on the sensitivity of silver halide emulsions.While the higher polyethyleneglycols have a considerable or remarkablesensitization effect, the utility of such compounds is limited by thefact that they cause marked increases in the fog levels of silver halideemulsions. It is known that the fog level increase cannot sufficientlybe controlled by the addition of antifoggants to the emulsion.

It is among the objects of the present invention to increase the generalsensitivity or speed of silver halide emulsion layers. A further objectis to provide photographic silver halide emulsions and emulsion layershaving an increased general sensitivity without concomitant increase infog level. Other objects will be apparent from the following description of the invention.

By the term general sensitivity it is intended to refer to thesensitivity of photographic emulsions through the whole spectrum. By theterm spectral sensitivity it is intended to refer to the sensitivity ofthe photographic emulsion to light ofa certain range of the spectmm.

It is the object of the invention to find new chemical sensitizers whichdo not have the above disadvantages and by means of which it is possibleto increase the sensitivity of photographic silver halide emulsionswithout causing unwanted fog formation.

It has now been found that the sensitivity of silver bromide emulsionscan be considerably increased without concomitant increase in fogging ifthe development of the exposed emulsion layers is performed in thepresence of 1,4-thiazanes-of the following formula:

in which R represents hydrogen or an alkyl group containing up to carbonatoms preferably methyl; and

R stands for (1) hydrogen, (2) a linear or branched alkyl groupcontaining up to 12 carbon atoms, preferably up to 5 carbon atoms, whichalkyl radicals may be substituted with phenyl, hydroxyl, cyano,carboxyl, esterified carboxyl or alkoxy groups, (3) aryl, especially aradical of the phenyl series which may be substituted, (4) acyl,especially acyl derived from aliphatic carboxylic acids preferablyhaving up to 5 carbon atoms, (5) carbamoyl in which the amide group maybe substituted with alkyl having preferably up to 5 carbon atoms,aralkyl such as benzyl, or aryl especially phenyl, or (6) an amino groupin which the hydrogen atoms may be substituted with alkyl groups,preferably alkyl having up to 5 carbon atoms, aryl, especially phenyl,or acyl, especially those of the type mentioned above; the amino groupmay in addition be substituted with carbamoyl groups which may in turnbe alkylated orphenylated.

If the nitrogen-atom of the morpholine ringis capable of forming simplesalts or quaternary ammonium salts, these may, of course, also be usedin the process according to the invention. Suitable quaternary groupsare alkyl groups containing up to 12 carbon atoms, preferably up to 5carbon atoms, which may be substituted, e.g. with phenyl groups as inbenzyl or phenyl ethyl groups.

Any anions may occur in these compounds, e.g. halides, perchlorates andthe like. As is well known, the nitrogen atom of the morpholine ringcannot be quatemized if the basic properties of the nitrogen aresuppressed by electro negative substituents. This occurs, e.g. when Risphenyl, carbamoyl or acyl. W

Particular utility is exhibited by thefollowing compounds:

F JLNHQ N- H -CHa s N-NH-ii-NHQ The substances for use according to theinvention are prepared from thiomorpholine in known manner. Thepreparation of thiomorpholine has been described in J. Chem. Soc. 1920,pp. 761-308; J. Am. Chem. Soc. 76 (1954), pp. 1187-1188; US. Patent2,761,860; DAS 1,104,513. The preparation of C-substituted 1,4-thiazanesare described in J. Am. Chem. Soc. 76 (1954), pp. 2902-2906.

1,4-Thiazanes substituted on the nitrogen atom are prepared from thecorresponding unsubstituted thiazane which is reacted according to knownprocesses with a suitable halogenated compound with the addition of acidbinding agents. The other compounds given above can be obtained byreacting unsubstituted thiazane with acid chlorides or with isocyanates.

N-Amino-1,4-thiazane can be prepared by introducing a nitroso group intothiazane followed by reduction.

The acid salts and quaternary salts are prepared by known methods.

The preparation of photographic silver halide emulsions.

includes 3 separate steps:

(1) Emulsification and physical ripening which is also called Ostwaldripening;

(2) the freeing of the emulsion of excess water soluble salts, usuallyby washing with water and drying, and

(3) the after ripening which is also called chemical ripening to obtainincreased emulsion speed or general sensitivity.

The sensitizers of the present invention can be added to the emulsionbefore, during or after the chemical ripening or they can be addedimmediately prior to the casting.

The particular quantity of the sensitizers of the invention used in agiven emulsion can vary, depending upon the effects desired, silvercontent of the emulsion, the silver halide composition etc. Generallythey are added in amounts of 3 mg. to 20 g. preferably 3 mg. to 6 g. permol of silver halide. The compounds are also effective when they areadded to the developer solution in which case they are preferably usedin similar quantities per liter of the aqueous developer bath.

The sensitizers can be dissolved in water or a solvent miscible withwater or a mixture of water and water-miscible solvents, and added inthis form to the emulsion. The solvent is not critical and should beselected so that it should have no harmful effect to the photographicproperties of the silver halide emulsion.

The optimum amount for any sensitizer of the present invention can bedetermined for any particular emulsion by running a series of comparisontests in which the quantity of the sensitizer is varied over a givenrange. Exposure of the emulsion containing the sensitizer in a mannerwell known and measuring of the sensitivity in conventional apparatuseswill reveal most advantageous concentrations. Such technique is wellunderstood by those skilled in the art.

The thiomorpholine derivatives of the invention are used in silverbromide emulsions wh ich may contain a small amount of silver iodide ofup to 10 mol percent.

The photographic emulsion in which the sensitizers according to theinvention are used, can be chemically sensitized by any of the knownprocedures. They can be sensitized, for example, with sulfur compoundsas referred to, e.g. in the book The Theory of the Photographic Process"by Mees (1954) pp. 149-161.

The emulsions can also be chemically sensitized with salts of noblemetal such as gold, ruthenium, rhodium, palladium, iridium and platinum,used in amounts below that which produce any substantial fog.Representative compounds are ammonium chloropalladate, potassiumchloroplatinate, potassium chloroaurite, potassium aurithiocyanate,potassium chloroaurate, auric trichloride and the like. The emulsionscan be sensitized with reducing agents, stannous salts or polyamines andthe like. The emulsions can also be optically sensitized with cyanine,merocyanine or rhodacyanine dyes.

The emulsions may also be optically sensitized, e.g. with the usualpolymethine dyes such as neutrocyanines, basic or acid carbocyanines,rhodacyanines, hemicyanines, styryl dyes, oxonoles and the like.Sensitizers of this type have been described in the work by F. M. Hamer(The Cyanine Dyes n R te Q g g qg 111? my ,7 W w,

The emulsions can be stabilized with any of the known stabilizers, e.g.homopolar or salt-type compounds of mercury with aromatic orheterocyclic compounds (for example mercaptotriazoles), simple mercurysalts, sulfonium mercury double salts and other mercury compounds. Othersuitable stabilizers include azaindenes, especially tetraorpentaazaindenes, in particular those which are substituted with hydroxylor amino groups. Such compounds have been described in the article byBirr, Z. Wiss. Phot. 47, 2-58 (1952). Other suitable stabilizers includeheterocyclic mercapto compounds, e.g. phenylmercaptotetrazole,quaternary benzothiazole derivatives, benzotriazole and the like.

The silver halide emulsion layers may contain any suitable film-formingand water-permeable colloid as binding agent, such as gelatin but thegelatin can be replaced partially with products like alginic acid andderivatives thereof such as salts, preferably with alkali metals, esterswith lower aliphatic alcohols or amides. The gelatin can also bepartially replaced with polyvinyl alcohol, polyvinyl pyrrolidone,starch, carboxymethyl cellulose and the like.

The emulsions may be hardened in the usual manner, for example, withformaldehyde or halogen-substituted aldehydes which contain a carboxylgroup, such as mucobromic acid, diketones, methanesulfonic acid esters,dialdehydes and the like.

The compounds according to the invention are effective for bothblack-white emulsions and for color photographic emulsions which containcolor couplers.

EXAMPLE 1 600 mg. of saponin as wetting agent, 200 mg. of 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene as stabilizer and 10 ml. of a 10%aqueous solution of formaldehyde are added to a silver iodobromidegelatin emulsion which contains 60 g. of silver per liter in the form ofsilver halide which has a silver iodide content of 6 mols percent.

The emulsion was divided into three equal samples and the followingsubstances were added per liter of emulsion to the individual samples:

Sample A: Comparison sample without additive Sample B: 300 mg. ofcompound 1 Sample C: 600 mg. of compound II] The casting solutions areapplied onto a support of cellulose triacetate, exposed in asensitometer customarily employed in the art behind a grey step wedgeand developed for 10 minutes in a developer of the followingcomposition:

Sodium sulfite anhydrous 70.0 g. borax 7.0 g. hydroquinone 3.5 g.p-monomethyl-aminophenol 3.5 g. sodium citrate 7.0 g. potassium bromide0.4 g.

make up to 1 liter with water The results of the sensitometric test aregiven in the following table:

An increase by 3 represents a sensitivity gain of one shutter stop ordouble sensitivity.

EXAMPLE 2 A silver iodobromide gelatin emulsion containing 4.5 5 molpercent silver iodide which has been ripened to optimum sensitivity withgold and sulfur compounds in known manner is sensitized by the additionof 45 mg. of the following sensitizing dye per kg. of emulsion:

In addition, the following ingredients are added per kg. of emulsion: g.of 1-(3'-sulfo-4'-phenoxy)-phenyl-3-heptadecyl-pyrazolone as magentacoupler; 250 mg. of 1,3,3a,7- tetraaza-4-hydroxy-6-methyl indene asstabilizer; ml. of a 5% aqueous solution of saponin as wetting agent;2.5 ml.

of a aqueous solution of formaldehyde as hardener.

The emulsion was divided into 7 equal samples and the followingsubstances were added per kg. of emulsion to the individual samples:

Sample A: Comparison sample without additive Sample B: 1.0 g. ofcompound I Sample C: 3.0 g. of compound I-II Sample D: 1.0 g. ofcompound XII Sample E: 1.0 g. of compound IV Sample F: 0.3 g. ofcompound XI Sample G: 1.0 g. of compound XIV The samples are appliedonto a support of cellulose acetate and dried. They are then exposedbehind a step wedge and processed in the usual manner. Processing iscarried out as follows:

Color development 7 minutes short stop bath 5 minutes washing 5 minutesbleaching bath 5 minutes washing 5 minutes fixing bath 5 minutes washing10 minutes The color developer has the following composition:

make up to 1 liter with water W v The color density of the magentalayers was determined with a Macbeth Quanta Log, Model TD- 102densitometer, a green color filter being interposed in the path of thebeam of measuring light.

TABLE 2 Sample Sensitivity Gamma Fog A Blank 0.61 0. 16 B 2.5 0.63 0.18

An increase by 3 here also represents double sensitivity or asensitivity increase of one shutter stop.

EXAMPLE 3 The thiomorpholine compounds of the invention are alsoeffective when applied in color developers, as illustrated by thefollowing Example. Each of the following substances is added to a colordeveloper in an amount of l g. per liter:

Sample A: Comparison sample without additive Sample B: compound I SampleC: compound 11 Sample D: compound XV (0.5 g. per liter).

The color developer has the following composition:Diethyl-p-pheny1enediamine sulfate 2.75 g., hydroxylamine sulfate 1.2g., sodium sulfite anhydrous 2.0 g., sodium hexametaphosphate 2.0 g.,potassium carbonate anhydrous 75.0 g., potassium bromide 2.0 g., make upto 1 liter with water.

A conventional commercial color photographic multilayer material havingon a support'a red-sensitive silver bromide emulsion layer with a cyancoupler, a green-sensitive emulsion layer with a magenta coupler and ablue-sensitive emulsion layer containing a yellow coupler, is exposedbehind a step wedge and processed in the usual manner.

Color development 7 minutes stop bath 2 minutes washing 15 minutesbleaching bath 5 minutes washing 5 minutes fixing bath 5 minutes washing10 minutes Intermediate bath, bleaching bath and fixing bath have thecompositionreferredto above.

The color densities of the individual layers of the multilayer materialare measured with a Macbeth Quanta Log, Model TD 102" densitometer, theappropriate color filter" being interposed in each case into the path ofthe beam.

An increase by 3 again denotes a sensitivity increase of one shutterstop or double the sensitivity.

We claim:

1. In a process for the production of photographic images by exposureand development of photographic materials which have atleast one silverbromide emulsion layer, the improvement consisting of developing theexposed" material in effective contact with a 1,4-thiazane of thefollowing formula:

S N-R in which R stands for hydrogen or alkyl containing up to carbonatoms and 5. The process of claim 1, wherein the 1,4-thiazane has thefollowing formula:

;.li qnsit terhrqm e at n em on taining per mol of silver bromide 3 mg.to 20 g of a 1,4- thiazane of the following formula:

S N-R in which R stands for hydrogen or alkyl containing up to 5 carbonatoms;

R represents (1) hydrogen, (2) a linear or branched alkyl groupcontaining up to 12 carbon atoms, (3) a radical of the phenyl series,(4) an aliphatic carboxylic acyl group having up to five carbon atoms,(5) a carbamoyl group, or (6) an amino group. 7. The emulsion of claim 6containing additionally up to 10 mol percent of silver iodide based onthe silver bromide.

8. The emulsion of claim 6, wherein R represents alkyl, substituted withphenyl, hydroxyl, cyano, carboxyl or alkoxy.

9. The light-sensitive emulsion according to claim 6,

in which the thiazine has the formula:

10. The light-sensitive emulsion according to claim 6,

in which the thiazane has the formula:

2. A process according to claim 1, wherein the compound containing atleast one diazosulphone group is present in an amount within the rangeof 0.01 to 5 percent by weight based on the weight of photopolymerisableethylenically unsaturated organic compound present.
 3. A processaccording to claim 1, wherein a light source is used emitting light inthe wavelength range of 2500-5000 A., particularly 3000-5000 A.
 4. Aprocess according to claim 1, wherein a light source is used emittinglight in the wavelength range of 2500-7000 A. and wherein aphotooxidation sensitizer of the class consisting of acridine,phenazine, thiazine or xanthene dyes is present in thephotopolymerisation composition in an amount between 0.001 and 0.1percent by weight with respect to the ethylenically unsaturated organiccompound present.
 5. A process according to claim 1, wherein thephotopolymerisation initiator is (phenylsulphonyl)-(p-tolyl)-diimide. 6.A process according to claim 1, wherein the photopolymerisationinitiator is (p-acetamidophenyl-sulphonyl)-(p-tolyl)-diimide.
 7. Aprocess according to claim 1, wherein the photopolymerisation initiatoris the sodium salt of (phenyl-sulphonyl)-(p-sulphophenyl)-diimide.
 8. Aprocess according to claim 1, wherein the photopolymerisation initiatoris (p-tolylsulphonyl)-(p-acetamidophenyl)-diimide.
 9. A processaccording to claim 1, wherein the photopolymerisation initiator is(m-carboxy-phenyl-sulphonyl)-(p-carboxyphenyl)-diimide.
 10. A process ofproducing a polymeric photographic relief image, which comprisesexposing to a pattern of actinic light radiation a photographic elementcomprising a support and a light-sensitive layer comprising aphotopolymerisable ethylenically unsaturated organic compound and as aphotopolymerisation initiator a compound containing at least onediazosulphone group, said compound corresponding to one of the formulae:X-SO2-N N-Y and X''-SO2-N N-Z-N N-SO2-X'' wherein: X represents phenyl,naphthyl, or phenyl substituted in ortho, meta or paraposition withrespect to the sulphonyl group by alkyl of one to four carbon atoms,carboxyl, amino, dialkylamino wherein the alkyl groups comprise one tofour carbon atoms, acylamino wherein the acyl group comprises two toseven carbon atoms, phenylazo or nitrophenylazo; X'' represents phenyl,aminophenyl or alkylphenyl wherein the alkyl group comprises one to fourcarbon atoms; Y represents pyridyl, anthraquinonyl, naphthyl, acridinyl,benzothiazolyl or a group of the formula
 11. A process according toclaim 10 wherein the pattern of actinic light radiation emits light inthe wavelength of 2500-5000 A., particularly 3000-5000 A.
 12. A processaccording to claim 10, wherein the pattern of actinic light radiationemits light in the wavelength of 2500-7000 A and wherein thelight-sensitive layer also comprises a photooxidation sensitizer of theclass consisting of acridine, phenazine, thiazine or xanthene dyes in anamount between 0.001 and 0.1 percent by weight with respect to theethylenically unsaturated organic compound present.